Unmodeled Projects Overview
Most project types in Visual Studio implement the Visual Studio automation model. Some projects, however, do not. When such a project is encountered while you are programming in the Visual Studio automation model, it is referred to as an unmodeled project.
Unmodeled projects are treated the same as modeled projects except that many of the project-related properties and methods do not work with them. Because the automation model cannot communicate with the project, certain details cannot be discovered or altered. You can only obtain basic information about such projects.
Following is a list of valid members (that apply to various objects and collections) for unmodeled projects:
Valid Unmodeled Project Members
If other properties or methods are used with an unmodeled project, either E_NOTIMPL or Nothing is returned.